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Hello World in Python [duplicate]

...print("Hello, World!") You are probably using Python 3.0, where print is now a function (hence the parenthesis) instead of a statement. share | improve this answer | follow...
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Adding a column to a data.frame

...1, 1 + cumsum(nonpos)) > classes [1] 1 1 1 1 2 2 2 2 2 2 2 3 3 3 3 Now, we can attach it back onto our data frame with cbind (by using the class= syntax, we can give the column the class heading): > data_w_classes <- cbind(data, class=classes) And data_w_classes now contains the re...
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What is a race condition?

...read scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the result of the change in data is dependent on the thread scheduling algorithm, i.e. both threads are "racing" to access/change the data....
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How do I configure Notepad++ to use spaces instead of tabs?

... Ah Language, now that makes sense. – deed02392 Dec 5 '13 at 16:05 ...
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Choosing a Java Web Framework now? [closed]

...ng for. I can't really talk about (recent versions) of Flex and GWT but I know that Grails does have some fans. Actually, I'd suggest to take a look at Matt Raible's presentations, he really did a great job at comparing web frameworks, showing their strengths and weakness, gathering facts and numb...
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Bash continuation lines

... Thanks for your help, but while this does remove the spaces, they are now separate parameters (Bash is interpreting the spaces on the second line as a parameter separator) and are now only printed correctly because of the echo command. – user880248 Sep 6 '...
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Rails 3 - can't install pg gem

...pplications/Postgres.app/Contents/MacOS/bin:$PATH" gem install pg should now work. (This is what worked for me.) Note New versions path looks like: /Applications/Postgres.app/Contents/Versions/<version>/bin share ...
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Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything

...un Docker build on various files which previously worked before, which are now no longer working. 14 Answers ...
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How to check if variable is string with python 2 and 3 compatibility

... in Python 2 in the most generic manner, isinstance(s, basestring) will now also work for Python 3+. share | improve this answer | follow | ...
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Summarizing multiple columns with dplyr? [duplicate]

...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R. ...